Safari is blocking my Facebook

I tried to block an ad which kept reccuring on my facebook page by right clicking the ad and then clicking "block ad"

A slider came up and I was told to slide to the right until the ad disappeared. So I did. The add disappeared but then returned almost immediatly.

After a couple of goes I moved the slider fully to the right. The ad disappeared, permanently but now for some strange reason I can't access facebook at all because safari seems to be blocking it. I can still access Facebook on my ipad,

Iv'e tried looking in security settings but cant find anything to solve the problem. I'm running Safari 10.6.8 snow leopard

Anyone have any ideas?

Thanks all

😕 😟